M135 Muffler

[USMC 00-08]

A man that I know who drove these in the US Army in the 1950's said they used to hollow the mufflers out to get better performance on the then new G749's. That is what I was wanting to test out. He said the sound was not that much louder after doing the modification.

-Can we just build a can and put ends on it or do we have other concerns like back pressure, tuning, dba?
- Can we maintain the amazing throaty sound and still go cheap? Build 2 styles? Hollow and packed?
- If "Restoring to the highest possible prestigious and original standard", do we need to re-create the inside of a muffler...to get points with the purists...and make them proud of what we did?

After fighting with my truck for a few weeks now, I finally got it running. Part of the problem was the stock muffler. It did not seem to be plugged, but as soon as I took it off, things started running a lot better. I have a hollowed out G749 muffler that needs an end welded back on it. I am going to try get that done tomorrow and then see how it works/sounds. I'll see if I can get a video of the before and after...no muffler/with hollow muffler.

 

[hambone]

My muffler is rotting out on the back end, I going to patch it up with the mig welder.

 

[USMC 00-08]

I took the hollow muffler with me to work today with the intention of stopping by the muffler shop afterwards. One of the guys at work who is a welder volunteered to weld it for me since he was slow today. The end of it was really thin so he cut off 2" to get back to good metal. We had some scrap stainless laying around and he put that on. Got it home, cleaned of the rust and painted it up with some header paint to prevent further corrosion. I plan to install it this weekend but am trying to figure out how to make a video to post up before I do.

 

[SturmTyger380]

Nice job!

 

[USMC 00-08]

Here is some video footage.

https://www.youtube.com/watch?v=xYMiR2DT7Fo

 

[metal magnet 1963]

M 135 "road warrior"

Here is some video footage.

https://www.youtube.com/watch?v=xYMiR2DT7Fo

I'm sitting here trying to wipe the drool off the keyboard! That unit sounds pretty darn good! When you were on the "open road", I thought you were doing something like 50, then you showed the speedo, and were doing 30!!!! the revs are sure high. It seems to shift ok, I can't run mine enough just yet, but I wish I could do like you. In time I guess. I think the "hollowed out muffler'" is just a bit too loud for normal operation, but when you ran with no muffler, it was the same roar I remember when I had my first M-135, what a sweet sound. Was deaf for a half hour after, but didn't mind!!!
Keep up the good work, and your going to see the results in time.

 

[USMC 00-08]

I would like to have it a little more quiet. For now the hollow muffler will have to do until plowboy gets the muffler build figured out.

If it turns out the mufflers are to expensive to ship south of the border, maybe his muffler man would be interested in selling prints on how to do it?

 

[metal magnet 1963]

Would be welcomed, for sure.

 

[m1010plowboy]

G749 Muffler

Prototype one to test for tuning, sound, function is done. We'll get it bolted on Goose real soon for testing. She's running a parade Saturday so trying to get it bolted on for that.

Once we're sure it's good enough to share we'll get an add up in the classifieds with more info. Vroom vroom.

 

[m1010plowboy]

New G749 Muffler

Finally found donuts so I could try out the new muffler. I did two videos but we just set the camera on the window frame so we'll need to get better sound bytes.



Original

https://youtu.be/1rodYyYn5CU

New

https://youtu.be/-MScILywFFE

This thing is quiet. We did a couple of 50mph runs and don't sense any performance change. The M135 is going on a 30mile jog back to Edmonton this week so we'll get a chance to get her real hot.




One thing we didn't do is add this reinforced neck ring around the flange. If someone is beating their muffler, unlike Goose the Asphalt Queen, then a collar might be needed.




Our next challenge is sourcing the 2 7/16 ID 3 OD 1/2" thick exhaust pipe donuts.......any new manufacturers out there?

 

[USMC 00-08]

I used these on mine.

https://www.napaonline.com/p/FPB60986


OD 2.95" ID 2.5" Thickness 1/2". Probably won't get much closer than that.

That muffler sounds real good.

 

[m1010plowboy]

G749 muffler

Took the big drive from the 5th meridian into Edmonton today and Goose was a rocket ship. It was so fast I was actually slowed down by a suburban most of the way in. Hit the 58mph mark and lifted the foot with only about 50% throttle input. I know we had a tail-wind but it seems like Goose is performing much better than before. I'm wondering if the old muffler was restrictive. I'll swap it back in and do more testing.



Found another Soldier who spent time on the trucks, the most memorable in Lars Germany from 82' to 85'. We went for a tour and he couldn't really tell any difference in the sound however the grin on his face told the rest of the story.

Sent a late note out to the fabricator so we'll start the conversation about what's next. I'd like to step aside and have folks order direct from him, deal with warranty, shipping etc. Ideally we ship a few crates into the U.S. and distribute from there. That doesn't mean that I won't help anyone in the Steel Soldiers group get a muffler if they're pushing for one sooner than later. I'll let the muffler men, Cole and Murray, dig up shipping info/costs so if someone on SS wants one let me know and I'll push from up here.

Goose did not want to go home until we caught a sunset shot so........, here it is!

 

[USMC 00-08]

I will probably be interested in 2 at some point. Not a big hurry yet as I am trying to get mine back together and painted first. Let me know the cost when they get it figured out.